Chromosomal replication initiates and terminates at random sequences but at regular intervals in the ribosomal DNA of Xenopus early embryos.
نویسندگان
چکیده
منابع مشابه
In Xenopus egg extracts, DNA replication initiates preferentially at or near asymmetric AT sequences.
Previous observations led to the conclusion that in Xenopus eggs and during early development, DNA replication initiates at regular intervals but with no apparent sequence specificity. Conversely, here, we present evidence for site-specific DNA replication origins in Xenopus egg extracts. Using lambda DNA, we show that DNA replication origins are activated in clusters in regions that contain cl...
متن کاملDNA replication timing is deterministic at the level of chromosomal domains but stochastic at the level of replicons in Xenopus egg extracts
Replication origins in Xenopus egg extracts are located at apparently random sequences but are activated in clusters that fire at different times during S phase under the control of ATR/ATM kinases. We investigated whether chromosomal domains and single sequences replicate at distinct times during S phase in egg extracts. Replication foci were found to progressively appear during early S phase ...
متن کاملDNA replication initiates at domains overlapping with nuclear matrix attachment regions in the xenopus and mouse c-myc promoter.
Only a very few origins have been mapped in different multicellular organisms, and they do not share detectable consensus sequence elements. Moreover, it is not clear if origins are localized at similar positions in the corresponding locus in genomes of different organisms. Here, we have mapped DNA replication origins in the c-myc locus both in Xenopus and mouse, allowing a comparison of the co...
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ژورنال
عنوان ژورنال: The EMBO Journal
سال: 1993
ISSN: 0261-4189
DOI: 10.1002/j.1460-2075.1993.tb06140.x